LCD Shutter Replacing Color Wheel in Projection Systems?

[dcau88]

Hi:

Has any one seen commercial implementations of using LCD shutter to
replace the mechanical color-wheel in projection engines based on
sequential color?

Are any manufacturers going this route? I've read some papers about
their use but haven't seen any offerings.

Any ideas?

Thanks!

Derek

 

[Sam Goldwasser]

Hi:

Has any one seen commercial implementations of using LCD shutter to
replace the mechanical color-wheel in projection engines based on
sequential color?

Are any manufacturers going this route? I've read some papers about
their use but haven't seen any offerings.

One fundamental problem is that you lose 2/3rds (approx) of the light
that way due to the other color pixels not be transmitting.

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[NSM]

Has any one seen commercial implementations of using LCD shutter to
replace the mechanical color-wheel in projection engines based on
sequential color?

What units do that?

N

 

[James Sweet]

Hi:

Has any one seen commercial implementations of using LCD shutter to
replace the mechanical color-wheel in projection engines based on
sequential color?

Are any manufacturers going this route? I've read some papers about
their use but haven't seen any offerings.

Any ideas?

Thanks!

Derek

I've never heard of it being done, LCDs are notoriously slow, and they block
a fair portion of the light even when active. Color wheels are effective and
established technology, the next step up from that is 3 panels.

 

[dcau88]

There are a new breed of LCDs based on ferroelectric. They are much
faster and may do the trick.

 

[dcau88]

Hi Sam:

Could you elaborate on your comment about the 2/3rds loss?

What about a device like this?

http://www.colorlink.com/products/pdfs/select.pdf

Which alters polarization and is not an absorbtive shutter?

Derek